1. Field of the Invention
The present invention relates to an actuator for a rotor blade of a helicopter. More particularly, the present invention relates to a BLDC motor based actuator that is integrated in the profile of a rotor blade of a helicopter. Still more particularly, the present invention relates to a BLDC motor based actuator, that is integrated in the profile of a rotor blade of a helicopter, for manipulating active control surfaces that control the orientation of a rotor blade for primary flight control (PFC) and higher-harmonic control (HHC).
2. Description of Prior Art
The performance of a helicopter in the military is highly critical during combat situations and training missions. The operation and performance of particularly, the rotor blades of the helicopter is significant to the overall operation of the helicopter. The vertical lift and the forward and lateral movement of the helicopter are all made possible by the operation of the rotor blades.
A swashplate around the rotating shaft of a helicopter is currently used to mechanically control the movement of individual blades to adjust their pitch around the azimuth for rotor thrust control (tilt of thrust and thrust magnitude). Recently, trailing-edge flaps have been used on the rotor blade in an attempt to control the higher harmonics of the blades during flight to minimize vibration and noise. Such flaps on the rotor blades are not capable of controlling the primary flight characteristics of the rotor blade. Currently, some helicopters in service rely on servo-flaps (attached to trailing edges) for primary flight control but still use the swashplate to transmit flight control commands to the flaps. However, rapid operation of the flaps to manipulate the orientation of the rotor blade for primary flight control as well as the higher harmonic control is needed.
Therefore, there exists a need for a device that can rapidly adjust the control surfaces, leading edge slats and trailing edge flaps, of the rotor blades of a helicopter to provide improved thrust and efficiency and to control the orientation of the blades to decrease the noise and vibration. Additionally, such a device preferably is fully integrated in the rotor blade of a helicopter.